Force corrplot to show trailing zeros in correlation matrix plot

I am using the mtcars dataset in R to plot a correlation matrix using the corrplot package. My issue is that I would like the 0.9 value between wt and disp to show as 0.90. I have noticed this is possible when I change the method argument to "number" instead of "shade" but I want my plot to use the "shade" argument.

Is there a way I can transform my data so that corrplot shows the trailing zero?

My code is below:

library(tidyverse)
library(corrplot)

data("mtcars")

corr_df = mtcars %>%
  select(mpg, disp, hp, drat, wt, qsec)

mat = cor(corr_df, method = "spearman")

corrplot(mat, method = "shade",  tl.col = "black", 
                         addCoef.col = "black", type = "lower",  
                         order = "original" , diag = F,
                         addgrid.col = "black", tl.srt = 45, number.digits = 2)

I've tried using the number.digits argument but when it's set to 2 digits the output is still 0.9 and when it's set to 3 digits the output becomes 0.899.

This is not currently implemented in the package and the package has not received any updates in some time.

An issue has been raised, and there is a pull request addressing the issue.

Until the pull request is accepted, the best you could do would be to install the patched version with:

devtools::install_github("the-mad-statter/corrplot@add_format")

Here is the output with the patched version:

library(tidyverse)
library(corrplot)

data("mtcars")

corr_df = mtcars %>%
  select(mpg, disp, hp, drat, wt, qsec)

mat = cor(corr_df, method = "spearman")

corrplot(mat, method = "shade",  tl.col = "black", 
                         addCoef.col = "black", type = "lower",  
                         order = "original" , diag = F,
                         addgrid.col = "black", tl.srt = 45, number.digits = 2)

^{Created on 2024-04-30 with reprex v2.1.0}